A blog that I commonly read: 43folders seems to be having some browser rendering bugs (this is where, because of some bit of design & the mammoth-ness that is a browser [thousands of lines of code, I am sure] collide and cause something to display funny). To combat this, they have requested that people submit screenshots to flickr under a particular tag. Nice idea! (And it seems to be working.)
Me? I just use: browsercam.com before, during, and after ever website design. Notable mention: browsershots.org (fewer browsers & options and also fewer pesos to play).
Mac users: trouble understanding the above image? Try this: http://flickr.com/photos/daveward/69888365/.